The specific aim of this application is to obtain partial support for a Gordon Research Conference on Fertilization and the Activation of Development. This conference will focus on modern molecular and cellular approaches to understanding the mechanisms of fertilization and the activation of development. The conference for 1983 will emphasize mechanisms of fertilization as they relate to the activation of the sperm and egg and on the role of fertilization in initiating the pathway of embryogenesis. It will begin with a consideration of specific components of the sperm and egg surfaces and how they are involved with gamete recognition and binding. The roles of small molecules as effectors of gamete activation in vertebrates and invertebrates will be presented. Rearrangements of the egg cortex at the time of and following fertilization will be discussed in terms of how changes in the organization of cytoskeletal elements are related to alteractions in intracellular calcium, sodium and pH. The dynamic changes that sperm chromatin undergoes will be considered as an example of nucleocytoplasmic interactions. Speakers will explore the extent to which in vitro systems of chromatin dispersion serve as models for processes of male pronuclear development in vivo. Finally, the macromolecular sequelae of zygote activation will be analyzed with particular attention to their relation to effectors of activation. This meeting is an attempt to bring together scientists who do not generally meet in the same place, but are working on problems that have important common strains. We expect to obtain new insights into on the relationship between specific molecular and cellular components of gametes and their roles in the initiation of embryogenesis, and thereby gain a much deeper understanding of the significance of fertilization as a process that actuates development.